.auth_table{
    /*设置相邻单元格的边框间的距离*/
    border-spacing: 0;
    /*表格设置合并边框模型*/
    border-collapse: collapse;
    text-align: center;
    width: 50%;
    border:1px solid silver;
}
.auth_tbody{
    display: block;
    height: 80px;
    overflow-y: scroll;
}
.auth_tbody_tr{
    display: block;
    height: 80px;
    overflow-y: scroll;
}
.auth_thead {
    display: table;
    width: 100%;
    table-layout: fixed;
}

/*关键设置：滚动条默认宽度是16px 将thead的宽度减16px*/
.auth_thead {
    width: calc( 100% - 1em)
}

.auth_thead_th {
    background: #ccc;
}

.tr_light{
    background: #fff8cc!important;
}